1. has => have

2. in => on

3. don't => doesn't

4. wills => will

n(K2O)=0.5 mol
K2O + H2O --> 2KOH
--(0.5)-----------1 mol
=> mKOH= b= 56g
Gọi m là khối lượng ban đầu của dd KOH 8% ban đầu, sau khi cho K2O vào dd, thì K2O bị hòa tan hết tạo ra dd KOH 21% có khối lượng là m+47 (theo định luật bảo toàn khối lượng.
ta có phương trình sau:
0.08m+56=0.21(m+47)
igải phương trình trên ta có nghiệm m=354.846 (g)

Chọn A

Nguồn âm là vật phát ra âm thanh!

gd là gì?

tô đen => click chuột phải chọn KTPT => ngay chỗ password => text

\(\frac{x}{3}=\frac{10}{15}\Rightarrow x=\frac{10.3}{15}=2\)

Thi IOE lớp 7 cấp trường (năm học 2016-2017) ca sáng - YouTube đề mik y chan z á

\(\frac{a}{b}=\frac{c}{d}\Rightarrow\frac{a}{c}=\frac{b}{d}\) => \(\frac{a}{c}+1=\frac{b}{d}+1\)=> \(\frac{a}{c}+\frac{c}{c}=\frac{b}{d}+\frac{d}{d}\)=> \(\frac{a+c}{c}=\frac{b+d}{d}\) => \(\frac{a+c}{b+d}=\frac{c}{d}=\frac{a}{b}\)

Vậy \(\frac{a+c}{b+d}=\frac{a}{b}\)

1. dressed / gets / he / at / six o'clock / .

He gets dressed at six o'clock.

2. Wednesday / on / we / English / have / .

We have English on Wednesday.

3. you / go / what / to / time / do / school / ?

What time do you go to school?

4. now / you / doing / what / are / ?

What are you doing now?

5. are / mountains / around / town / there / many / and / rivers / our / .

There are many mountains and rivers arround our town.

6. books / the / table / are / Thu's / on.

Thu's books are on the table.

7. play / school / we / volleyball / after.

We play volleybal after school.

8. How / floors / school / does / many / have / your / ?

How many floors does your school have?